Cracking and non-adherence of the coating of ice cream bars during consumption is one of the major causes of complaints from consumers. It is not only messy but also it prevents the consumer from eating the entire coated product. An examination of store purchased coated ice creams showed that in numerous instances cracking had occurred and a significant percentage of the coating had fallen off. The cracking of the coating could be due to several reasons, such as ice cream shrinkage, temperature abuse or the composition of the ice cream and the coating, and may also be due to poor adhesion of the coating to the ice cream.
One method for solving this problem is disclosed in U.S. Pat. No. 2,191,352 to Oprean. The '352 reference discloses a confection comprising a frozen core or center surrounded by a coating of an edible gelatinous substance which substantially prevents cracking or flaking of the coating from the core when the product is consumed. If desired, the gelatinous coating material may be blended with flavoring materials such as chocolate liquor. However, as recognized in a later patent to the same inventor, i.e., U.S. Pat. No. 2,801,922 (see col. 1, lines 56-71), in products produced with the coating of the '352 patent, the components never blend together and the core and coating cannot be eaten as one. Thus, "[t]he product of said patent is a `somewhat chewy and cold-eating piece`" (see col. 1, lines 70-71 of the '922 patent).
The Oprean '922 patent attempts to remedy the deficiencies noted in the earlier '352 patent by providing a cushioning edible sheath around the frozen core. This sheath is composed of an emulsion of a gelatinous substance in an edible solvent having decomposed therein "large quantities of discrete, relatively insoluble gaseous air particles" which form gelatinous bubbles and suction-like cups to mechanically bind to an inner face of an outer chocolate coating layer. As the air cannot be solidified or completely frozen within the gelatinous matrix, however, the coating material is a very soft, sticky mushy material in its semi-liquid and set form (see, e.g., col. 5, lines 71-72). Moreover, the amount and disposition of the entrapped air must be carefully monitored and controlled during production which adds significantly to the cost and complexity of the manufacturing process.
U.S. Pat. No. 1,638,548 discloses, on p. 3 at col. 1 (lines 60-62), the formation of a frozen ice confection with two coating layers, e.g., a first gelatinous coating layer followed by an outer oleaginous coating of, for example, chocolate. However, as noted for instance in the Oprean '922 patent discussed above, the interposition of such a gelatinous coating layer between the frozen core and an outer chocolate coating produces a "somewhat chewy and cold-eating piece".
Subsequent methods for improving the adhesion of fat-based coatings to ice confections using a precoating or interface layer between the ice confection and the edible fat-based coating includes, for example, WO91/01649 which discloses a method for enhancing the adherence of coatings to frozen fat-based confections such as ice cream by applying a composition to the surface of a frozen fat-based confection as an interface layer between the frozen fat-based confection and the coating, wherein the interface layer composition comprises an effective amount of an edible polysaccharide, e.g., maltodextrin, in an aqueous solution, to enhance the adherence of the coating to the confection. WO95/21536 discloses an ice confection having a coverture layer on at least part of its surface, the layer including a first, inner, precoating layer. The precoating layer may have a similar or a different composition to the outer coverture layer and contains from about 25% to about 100% fat.